/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package cn.dengta.context.rpc;

import java.io.IOException;
import java.io.OutputStream;

import com.alibaba.fastjson2.JSONB;
import com.alibaba.fastjson2.JSONWriter;
import org.apache.dubbo.common.serialize.ObjectOutput;
import org.apache.dubbo.common.serialize.fastjson2.Fastjson2CreatorManager;
import org.apache.dubbo.common.serialize.fastjson2.Fastjson2SecurityManager;

/**
 * FastJson object output implementation
 */
public class FastJson2ObjectOutput implements ObjectOutput {

	private final Fastjson2CreatorManager fastjson2CreatorManager;

	private final Fastjson2SecurityManager fastjson2SecurityManager;

	private volatile ClassLoader classLoader;
	private final OutputStream os;

	public FastJson2ObjectOutput(Fastjson2CreatorManager fastjson2CreatorManager,
	                             Fastjson2SecurityManager fastjson2SecurityManager,
	                             OutputStream out) {
		this.fastjson2CreatorManager = fastjson2CreatorManager;
		this.fastjson2SecurityManager = fastjson2SecurityManager;
		this.classLoader = Thread.currentThread().getContextClassLoader();
		this.os = out;
		fastjson2CreatorManager.setCreator(classLoader);
	}

	@Override
	public void writeBool(boolean v) throws IOException {
		writeObject(v);
	}

	@Override
	public void writeByte(byte v) throws IOException {
		writeObject(v);
	}

	@Override
	public void writeShort(short v) throws IOException {
		writeObject(v);
	}

	@Override
	public void writeInt(int v) throws IOException {
		writeObject(v);
	}

	@Override
	public void writeLong(long v) throws IOException {
		writeObject(v);
	}

	@Override
	public void writeFloat(float v) throws IOException {
		writeObject(v);
	}

	@Override
	public void writeDouble(double v) throws IOException {
		writeObject(v);
	}

	@Override
	public void writeUTF(String v) throws IOException {
		writeObject(v);
	}

	@Override
	public void writeBytes(byte[] b) throws IOException {
		os.write(b.length);
		os.write(b);
	}

	@Override
	public void writeBytes(byte[] b, int off, int len) throws IOException {
		os.write(len);
		os.write(b, off, len);
	}

	@Override
	public void writeObject(Object obj) throws IOException {
		updateClassLoaderIfNeed();
		byte[] bytes;
		if (fastjson2SecurityManager.getSecurityFilter().isCheckSerializable()) {
			bytes = JSONB.toBytes(obj, JSONWriter.Feature.WriteClassName,
					JSONWriter.Feature.FieldBased,
					JSONWriter.Feature.ErrorOnNoneSerializable,
					JSONWriter.Feature.ReferenceDetection,
					JSONWriter.Feature.WriteNulls,
					JSONWriter.Feature.NotWriteDefaultValue,
					JSONWriter.Feature.NotWriteHashMapArrayListClassName,
					JSONWriter.Feature.WriteNameAsSymbol);
		} else {
			bytes = JSONB.toBytes(obj, JSONWriter.Feature.WriteClassName,
					JSONWriter.Feature.WriteEnumsUsingName,
					JSONWriter.Feature.FieldBased,
					JSONWriter.Feature.ReferenceDetection,
					JSONWriter.Feature.WriteNulls,
					JSONWriter.Feature.NotWriteDefaultValue,
					JSONWriter.Feature.NotWriteHashMapArrayListClassName,
					JSONWriter.Feature.WriteNameAsSymbol);
		}
		writeLength(bytes.length);
		os.write(bytes);
		os.flush();
	}

	private void updateClassLoaderIfNeed() {
		ClassLoader currentClassLoader = Thread.currentThread().getContextClassLoader();
		if (currentClassLoader != classLoader) {
			fastjson2CreatorManager.setCreator(currentClassLoader);
			classLoader = currentClassLoader;
		}
	}

	private void writeLength(int value) throws IOException {
		byte[] bytes = new byte[Integer.BYTES];
		int length = bytes.length;
		for (int i = 0; i < length; i++) {
			bytes[length - i - 1] = (byte) (value & 0xFF);
			value >>= 8;
		}
		os.write(bytes);
	}

	@Override
	public void flushBuffer() throws IOException {
		os.flush();
	}

}
